Revert "Use existing convention of using finish_key"

This reverts commit 670cf52ccf84f4bfbf4602c5117c78889808fa6d.
Revert "Fix edge case with repeated calls"

This reverts commit d930edd47d6db85bf8d45a15b4b4aff6250d9ed5.
Revert "Fix _get_range and support tokens with key_count"

This reverts commit de9ec9e919bbda2928d4646c2250efa8855af14a.
Revert "Allow mix start_key and end_token"

This reverts commit 5e05d233b6d78cc57934257592ec921262b03ca1.